校长的时间分配及其与学生表现和学校环境的关系

El rol de director escolar conlleva la ejecución de múltiples actividades que, muchas veces, van en paralelo con la actividad didáctica lo que podría estar relacionado con rendimiento y clima escolar. Por esta razón, la investigación persigue tres objetivos: i) describir las actividades llevadas a cabo por los directores escolares; ii) identificar quiénes acompañan a los directores en las distintas actividades; iii) analizar la relación entre las actividades directivas con el rendimiento de la escuela. Hemos optado por un estudio cuantitativo en el que se analizan las prácticas diarias de 42 directores de escuelas con buen rendimiento escolar y 42 directores de escuelas con bajo rendimiento escolar, según los resultados de las Pruebas Nacionales. Para identificar la frecuencia de ejecución de actividades se utilizó un Registro Diario. Por otro lado, se utilizó una escala para medir el clima escolar. Los resultados indican que los directores de los distintos grupos conformados, distribuían el tiempo de gestión en las 10 actividades directivas identificadas, arrojando como resultado que las actividades a las que los directores invertían más tiempo fueron: 1) No escolares; 2) Relaciones con los estudiantes; 3) Liderazgo Instructivo y Planear metas. Las actividades que menos tiempo recibían fueron: 1) Crecimiento profesional; 2) Finanzas; 3) Infraestructura. Con relación a los tipos de acompañamientos que tuvieron los directores escolares, en el grupo de las escuelas clasificadas por su rendimiento y por el clima escolar, no se obtuvieron diferencias. Los directores realizaron esta actividad con los siguientes tipos de acompañamientos: En primer lugar, Solo (sin acompañantes); en segundo lugar, acompañados de Profesores líderes, facilitadores y maestros. En tercer lugar, con vendedores y contratistas. Por último, no se evidenció una fuerte correlación entre las actividades que realiza el director y el rendimiento escolar.The role of school principal involves the execution of multiple activities that, many times, go in parallel with the teaching activity which could be related as performance and school climate. For this reason, the research has three objectives: i) to describe the activities carried out by school principals; ii) to identify who accompanies the principals in the different activities; iii) to analyze the relationship between the management activities and the school’s performance. We have opted for a quantitative study in which the daily practices of 42 principals of schools with good school performance and 42 principals of schools with low school performance are analyzed, according to the results of the National Tests. A Daily Record was used to identify the frequency of execution of activities. On the other hand, a scale was used to measure the school climate. The results indicate that the principals of the different groups formed, distributed the management time in the 10 directive activities identified, giving as a result that the activities to which the principals invested more time were: 1) Non-schools; 2) Relations with students; 3) Instructional Leadership and Goal Planning. The activities that received the least amount of time were: 1) Professional growth; 2) Finance; 3) Infrastructure. In relation to the types of accompaniment that the school principals had, in the group of schools classified by their performance and by the school climate, no differences were obtained. The principals carried out this activity with the following types of accompaniment First, alone (without accompaniment); second, accompanied by lead teachers, facilitators, and teachers. Thirdly, with vendors and contractors. Finally, there was no strong correlation between the activities carried out by the director and school performance.Роль директора школы предполагает выполнение множества мероприятий, которые во многих случаях идут параллельно с дидактической деятельностью, что может быть связано с успеваемостью в школе и школьным климатом. По этой причине исследование преследует три цели: i) описать деятельность, осуществляемую директорами школ; ii) определить, кто сопровождает директоров в различных видах деятельности; iii) проанализировать связь между управленческой деятельностью и результатами работы школы. Мы выбрали количественное исследование, в котором мы анализируем повседневную практику 42 директоров школ с хорошей успеваемостью и 42 директоров школ с низкой успеваемостью, согласно результатам Национальных тестов. Для определения частоты выполнения действий использовалась ежедневная запись. С другой стороны, для измерения климата в школе использовалась шкала. Результаты показывают, что директора различных сформированных групп распределяли свое время на управление среди 10 выявленных управленческих мероприятий, показывая, что мероприятия, в которые директора вкладывали наибольшее количество времени, были: 1) внешкольные мероприятия, 2) взаимоотношения с учащимися, 3) учебное руководство и цели планирования. Наименьшее количество времени получили следующие виды деятельности: 1) Профессиональный рост, 2) Финансы, 3) Инфраструктура. Что касается видов аккомпанемента, которые имели директора, то в группе школ, классифицированных по успеваемости и школьному климату, различий не было. Принципалы осуществляли эту деятельность со следующими видами сопровождения: Во-первых, один (без сопровождающих); во-вторых, в сопровождении ведущих преподавателей, наставников и учителей. В-третьих, с поставщиками и подрядчиками. Наконец, не было тесной взаимосвязи между деятельностью, осуществляемой директором, и успеваемостью школы.校长的角色涉及对学校不同活动的执行，这些活动很多时候与教学活动同时进行，因此我们认为其会影响学生表现和学校的氛围。本研究的目的有三个: i）描述校长开展的活动； ii）确定陪同校长参加不同活动的人员； iii）分析管理活动与学生表现之间的关系。我们进行了定量研究，根据国家测试的结果，对42名学业成绩好的学校校长和42名学业成绩差的学校校长的日常工作进行了分析。为了确定工作的执行频率，研究对其进行了每日记录。另一方面，研究使用了一个量表来测量学校的氛围。结果表明，在被确认的10项管理活动中，不同组校长对其时间分配最多的为：1）非学校活动，2）与学生有关，3）教学领导和目标计划。时间分配较少的活动为: 1）教师成长，2）财务，3）基础设施。在陪同校长人员类型方面，我们没有观察到其与学生成绩和学校环境的联系。陪同校长参加不同活动的人员类型为: 首先，无人员陪伴; 其次，由教师代表或其他老师陪同; 第三，由销售者和合伙人陪同。最后，研究未发现在校长开展的活动与学生表现之间存在强烈的相关性

Spectral element modeling of three dimensional wave propagation in a self-gravitating Earth with an arbitrarily stratified outer core

This paper deals with the spectral element modeling of seismic wave propagation at the global scale. Two aspects relevant to low-frequency studies are particularly emphasized. First, the method is generalized beyond the Cowling approximation in order to fully account for the effects of self-gravitation. In particular, the perturbation of the gravity field outside the Earth is handled by a projection of the spectral element solution onto the basis of spherical harmonics. Second, we propose a new formulation inside the fluid which allows to account for an arbitrary density stratification. It is based upon a decomposition of the displacement into two scalar potentials, and results in a fully explicit fluid-solid coupling strategy. The implementation of the method is carefully detailed and its accuracy is demonstrated through a series of benchmark tests.Comment: Sent to Geophysical Journal International on July 29, 200

Time allocation of principals and its relationship to school performance

El rol de director escolar conlleva la ejecución de múltiples actividades que, muchas veces, van en paralelo con la actividad didáctica lo que podría estar relacionado con rendimiento y clima escolar. Por esta razón, la investigación persigue tres objetivos: i) describir las actividades llevadas a cabo por los directores escolares; ii) identificar quiénes acompañan a los directores en las distintas actividades; iii) analizar la relación entre las actividades directivas con el rendimiento de la escuela. Hemos optado por un estudio cuantitativo en el que se analizan las prácticas diarias de 42 directores de escuelas con buen rendimiento escolar y 42 directores de escuelas con bajo rendimiento escolar, según los resultados de las Pruebas Nacionales. Para identificar la frecuencia de ejecución de actividades se utilizó un Registro Diario. Por otro lado, se utilizó una escala para medir el clima escolar. Los resultados indican que los directores de los distintos grupos conformados, distribuían el tiempo de gestión en las 10 actividades directivas identificadas, arrojando como resultado que las actividades a las que los directores invertían más tiempo fueron: 1) No escolares; 2) Relaciones con los estudiantes; 3) Liderazgo Instructivo y Planear metas. Las actividades que menos tiempo recibían fueron: 1) Crecimiento profesional; 2) Finanzas; 3) Infraestructura. Con relación a los tipos de acompañamientos que tuvieron los directores escolares, en el grupo de las escuelas clasificadas por su rendimiento y por el clima escolar, no se obtuvieron diferencias. Los directores realizaron esta actividad con los siguientes tipos de acompañamientos: En primer lugar, Solo (sin acompañantes); en segundo lugar, acompañados de Profesores líderes, facilitadores y maestros. En tercer lugar, con vendedores y contratistas. Por último, no se evidenció una fuerte correlación entre las actividades que realiza el director y el rendimiento escolar.The role of school principal involves the execution of multiple activities that, many times, go in parallel with the teaching activity which could be related as performance and school climate. For this reason, the research has three objectives: i) to describe the activities carried out by school principals; ii) to identify who accompanies the principals in the different activities; iii) to analyze the relationship between the management activities and the school’s performance. We have opted for a quantitative study in which the daily practices of 42 principals of schools with good school performance and 42 principals of schools with low school performance are analyzed, according to the results of the National Tests. A Daily Record was used to identify the frequency of execution of activities. On the other hand, a scale was used to measure the school climate. The results indicate that the principals of the different groups formed, distributed the management time in the 10 directive activities identified, giving as a result that the activities to which the principals invested more time were: 1) Non-schools; 2) Relations with students; 3) Instructional Leadership and Goal Planning. The activities that received the least amount of time were: 1) Professional growth; 2) Finance; 3) Infrastructure. In relation to the types of accompaniment that the school principals had, in the group of schools classified by their performance and by the school climate, no differences were obtained. The principals carried out this activity with the following types of accompaniment First, alone (without accompaniment); second, accompanied by lead teachers, facilitators, and teachers. Thirdly, with vendors and contractors. Finally, there was no strong correlation between the activities carried out by the director and school performance

Multimethod Characterization of the French-Pyrenean Valley of Bagnères-de-Bigorre for Seismic-Hazard Evaluation: Observations and Models

International audienceA narrow rectilinear valley in the French Pyrenees, affected in the past by damaging earthquakes, has been chosen as a test site for soil response characteriza- tion. The main purpose of this initiative was to compare experimental and numerical approaches. A temporary network of 10 stations has been deployed along and across the valley during two years; parallel various experiments have been conducted, in particular ambient noise recording, and seismic profiles with active sources for struc- ture determination at the 10 sites. Classical observables have been measured for site amplification evaluation, such as spectral ratios of horizontal or vertical motions between site and reference stations using direct S waves and S coda, and spectral ratios between horizontal and vertical (H/V) motions at single stations using noise and S-coda records. Vertical shear-velocity profiles at the stations have first been obtained from a joint inversion of Rayleigh wave dispersion curves and ellipticity. They have subsequently been used to model the H/V spectral ratios of noise data from synthetic seismograms, the H/V ratio of S-coda waves based on equipartition theory, and the 3D seismic response of the basin using the spectral element method. General good agreement is found between simulations and observations. The 3D simulation reveals that topography has a much lower contribution to site effects than sedimentary filling, except at the narrow ridge crests. We find clear evidence of a basin edge effect, with an increase of the amplitude of ground motion at some distance from the edge inside the basin and a decrease immediately at the slope foot

Modelling Seismic Wave Propagation for Geophysical Imaging

International audienceThe Earth is an heterogeneous complex media from the mineral composition scale (10−6m) to the global scale ( 106m). The reconstruction of its structure is a quite challenging problem because sampling methodologies are mainly indirect as potential methods (Günther et al., 2006; Rücker et al., 2006), diffusive methods (Cognon, 1971; Druskin & Knizhnerman, 1988; Goldman & Stover, 1983; Hohmann, 1988; Kuo & Cho, 1980; Oristaglio & Hohmann, 1984) or propagation methods (Alterman & Karal, 1968; Bolt & Smith, 1976; Dablain, 1986; Kelly et al., 1976; Levander, 1988; Marfurt, 1984; Virieux, 1986). Seismic waves belong to the last category. We shall concentrate in this chapter on the forward problem which will be at the heart of any inverse problem for imaging the Earth. The forward problem is dedicated to the estimation of seismic wavefields when one knows the medium properties while the inverse problem is devoted to the estimation of medium properties from recorded seismic wavefields

Modélisation numérique de la propagation d'ondes sismiques en géométrie sphérique : application à la sismologie globale

This work aims at developing a numerical tool to model 3D sei smic waves propagation at a global scale for realistic velocity and density distributions. We consider the eIastodynamics equations for an elastic and isotropic medium and we further take into account the gravity effects in the Cowling approximation for an initial state of hydrostatic equilibrium. We first present a finite difference modeling of long-period (~ 30 s) SH waves propagation in an axisymmetric Earth's mantle without gravity. In this framework, we study the influence of topography and velocity variations on the seismic waves reflected under the upper mantle's discontinuities. We then develop a spectral element method to model the full wavefield propagation in spherical geometry. We use a non-conforming hexaedrical mesh for the sphere in order to adapt the discretization to the variation of elastic parameters in the medium. The space of Lagrange multipliers related to the continuity constraints across the non-conforming interfaces is discretized by a mortar method that becomes conforming due to the spherical geometry. Fluid regions are taken into account by constructing a Dirichlet to Neumann operator that couples the spectral element method to a modes summation technique. The final method is validated for radially heterogeneous models by comparing the synthetic seismogramms to those produced by a normal modes method. Both parallel implementation and global cost of the method are discussed and perspectives to this work are proposed. The method's potentiality allows for the first time to compute the full seismic response of 3D Earth's models for period smaller than 50 seconds.Ce travail est consacre au développement d'un outil numérique capable de modéliser la propagation 3D d'ondes sismiques à l'échelle du globe pour des distributions réalistes de vitesse et de densité. On considère les équations de l 'élastodynamique en milieu élastique isotrope et on inclut les effets de la gravité dans l'approximation de Cowling pour un état initial d'équilibre hydrostaotique. On présente d'abord une approximation aux différences finies pour modéliser la propagation des ondes S H longue période (~ 30 s) dans un manteau terrestre axisymétrique en négligeant la gravité. Dans cette description, on étudie l'effet de variations de topographie et de vitesse sur les ondes réfléchies sous les discontinuités du manteau. On développe ensuite une méthode d'éléments spectraux permettant la modélisation 3D du champ d'ondes complet en géométrie sphérique. On utilise un maillage hexaédrique non-conforme de la sphère qui s'adapte à la variation des paramètres élastiques du milieu. L'espace des multiplicateurs de Lagrange associés aux contraintes de continuité sur les interfaces non-conformes est discrétisé par une méthode de joints qui devient conforme en géométrie sphérique. La prise en compte de régions fluides est basée sur la construction d'un opérateur Dirichlet to Neumann qui couple la méthode des éléments spectraux à une méthode de sommation de modes. La méthoge est validée dans des milieux homogènes par couches puis pour des modèles de Terre moyens, en comparant les sismogrammes obtenus avec ceux calculés par une méthode de modes propres. L'implémentation parallèle et le coût de calcul de la méthode sont présentés et les perspectives sont discutées. La potentialité de la méthode permet d'envisager pour la première fois de modéliser la propagation du champ d'ondes complet dans des modèles de Terre 3D pour des périodes inférieures à 50 secondes

Spectral element modeling of three dimensional wave propagation in a self-gravitating Earthwith an arbitrarily stratified outer core

Sent to Geophysical Journal International on July 29, 2003.This paper deals with the spectral element modeling of seismic wave propagation at the global scale.Two aspects relevant to low-frequency studies are particularly emphasized.First, the method is generalized beyond the Cowling approximation in order to fully account forthe effects of self-gravitation.In particular, the perturbation of the gravity field outside the Earth is handled by a projection of thespectral element solution onto the basis of spherical harmonics.Second, we propose a new formulation inside the fluid which allows to account for anarbitrary density stratification.It is based upon a decomposition of the displacement into two scalar potentials, and results ina fully explicit fluid-solid coupling strategy.The implementation of the method is carefully detailed and its accuracy is demonstrated through a seriesof benchmark tests

Different Fault Implementation for Earthquake Dynamic-Rupture modeling.

National audienceWe present large scale Dynamic Rupture simulations for a normal fault in SuperShear Mode inside various half-spaces. Our simulation are done with Lagrange Multiplier method on non-matching grids in Large Deformation and we compare the rupture front on the fault as well as the free-surface wave fields with the one obtained by other contact algorithm implementations

Solving elastodynamics in a fluid-solid heterogeneous sphere: a parallel spectral element approximation on non-conforming grids.

International audienc